1. Field of the Invention
The present invention relates to an image processing apparatus and an image processing method, which are capable of performing a compression encoding and a decoding with respect to image data.
2. Description of the Related Art
In resent years, there has been known a system to pick up an image, which has been captured by an optical microscope, in a digital form, and to save or display the image as a digital image. In the above-mentioned system, it is desirable that the picked-up digital image can be observed with operability equal to or higher than that of a real microscope.
For example, when a sample having some thickness is observed by a microscope optical system with a small depth of field, an operation of changing a focus position through rotating a slow-motion focus screw is necessary. In order to realize this operation in the above-mentioned system, a plurality of focus face images, which are obtained by imaging the same sample at a plurality of focus positions, are necessary. Thus, an enormous amount of image data is necessary to observe one sample, and hence, in the above-mentioned system, it is desirable to efficiently compress the image data.
For example, Japanese Patent Application Laid-open No. 2007-11977 (hereinafter, referred to as Patent Literature 1) discloses a compression method including using an inter-frame encoding with respect to a plurality of focus face images. In the inter-frame encoding, a difference is determined between frames adjacent to each other. In addition, Patent Literature 1 also refers to a compression method including using a predicted image, which is generated through performing a blur-compensation prediction with respect to a focus face image being the reference. For example, when a focus face image is desired to be compressed, a blur-compensation prediction, which depends on a distance between a focus face thereof and a focus face being the reference, is performed with respect to a reference focus face image. Then, difference data between the generated predicted image and the focus face image to be compressed is encoded (see, paragraphs [0030], [0033], and the like in Patent Literature 1).